eAJKD: Is this the first randomized clinical trial to test the effect of renal artery stenting versus medical therapy on left ventricular hypertrophy (LVH) progression in patients with ischemic heart disease and renal artery stenosis?

CM: Yes, for those specific endpoints.

eAJKD:What prompted you to evaluate LVH as an endpoint?

CM: We know there is a relationship between renal artery stenosis and high cardiovascular risk, mostly in patients with coronary artery disease. Prior studies have shown that there is a greater prevalence of LVH in patients with renal artery stenosis. Hence, we wanted to see if relieving renal artery stenosis would improve LVH. There are some retrospective studies showing some regression of LVH after revascularization.

Furthermore, cardiologists routinely identify renal artery stenosis while performing a coronary angiogram, and subsequently stent the renal vessels. Is there any evidence for this? We wanted to see the hard outcomes. While the study was ongoing, with our data showing that it doesn’t offer any benefits, practice patterns in our center began to change.

eAJKD:Based on the recent ASTRAL trial, would have altered your study design?

CM: Yes. The ASTRAL trial was a randomized, unblinded trial of 806 patients with atherosclerotic renovascular disease assigned to either renal artery revascularization while also receiving medical therapy or to medical therapy alone. The median follow-up was 34 months. They found substantial risks but no evidence of a worthwhile clinical benefit from revascularization in patients with atherosclerotic renovascular disease. Most of our patients had coronary artery disease and atherosclerotic renovascular disease, similar to the ASTRAL population. In retrospect, we would have included patients with renal artery stenosis greater than 80%.

eAJKD:When nephrologists encounter the question of whether to treat renal artery stenosis either medically or with stenting, it is often in the setting of poorly controlled hypertension or chronic kidney disease, neither of which was really prevalent in your study patients. How should nephrologists can apply your RASCAD findings to their practice?

CM: RASCAD confirms the findings of the ASTRAL and the STAR trials, and suggests individualizing the treatment of renal artery stenosis. If there is refectory hypertension or declining kidney function, revascularization might be of benefit.

eAJKD: What do you think is the biggest strength of your study?

CM: The strength of our study is the methodologic approach of randomizing all patients with renal artery stenosis, without introducing any bias of physician referral. Also, we asked a specific question in a selected population with coronary artery disease. This makes for a stronger study as it addresses one specific question systematically in a homogenous population. Also, our end point is structural (LVH).